Why Your Fruit Tree Doesn’t Have Fruit
Help! My apple tree is not producing
It can be frustrating to set out and care for apple, pear, and other fruit trees but never get a fruit. Understanding the basic principles of fruit production can help to explain why fruit trees fail to bear.
One of the reasons that trees fail to bear is simply that they are too young. Most fruit trees have a juvenile stage, in which they do not flower, of two to five years. Dwarf varieties will bear sooner than semi-dwarf or full-size trees.
Successful fruit production requires flowering, pollination, and fertilization, but there are many ways that these processes can be disrupted.
In order for flower buds to form on a branch, it must get sunlight. Overgrown trees often have fewer fruit buds than trees that are pruned regularly. Their flowers may be only on the ends of the branches, since sunlight can’t make it through the overgrown canopy. Fruit trees should be pruned annually to maximize the amount of sunlight that gets into the canopy of the tree.
Fertilization can also affect the bearing of fruit trees. While too little nutrients can be an issue, more often it is too much nutrients. Excess nitrogen, a key nutrient in plant development, will result in trees with lots of leaves but few fruit.
Cold weather can also affect both flower and fruit development. A certain amount of cold is required for trees to flower, but extremely low winter temperatures can kill flower buds and immature fruit.
To avoid this type of damage with peaches, select varieties rated at 750 chilling hours (a measure of the amount of cold weather it takes before the tree will flower) or more. Flowers damaged by cold weather will have a brown to black center. Fruit damaged by low temperatures will begin falling off about three weeks after the freeze.
Even if flowers develop and bloom, if they are not pollinated, fruit will not form. Pollination happens when pollen is moved from the male to the female part of the plant. Both wind and bees pollinate fruit trees. Windy, cold, wet weather when trees are in bloom reduces bee activity, and therefore pollination. Also, bees can be killed if certain insecticides are applied while trees are blooming.
After pollination, fruit will form only if the pollen is compatible with the flower. Many fruit trees, like most plums, apples, and pears are not self-fruitful. These trees require cross-pollination (pollen from another variety) to produce fruit. (Peaches and nectarines are self-fruitful and do not require another tree for pollination.)
So how do you know what trees will pollinate one another? Compatibility charts listing varieties and their cross-pollinators are available online or by calling the Extension office. Cross-pollinating trees should be within 50 to 100 feet of one another.
Golden Delicious (a self-fruitful apple variety) is a good pollenizer for most other apple varieties. Gravenstein, Jonagold, Stayman, and Winesap apple varieties are poor pollen-producers, so they should be planted with at least two other varieties to ensure adequate fruit set.